I have a 2003 Hyundai Sonata that in the past 2 weeks has started stalling after I add gas to the car. I have to rev the engine a few times, and then, when it feels like the car won't stall, I put the car in Drive and release the brake pedal. The car runs fine until the next time I add gas. This started right after I had my oil changed at one of the 30-minute oil change places so I don't know if it is a coincidence that this problem started then or if something was done to my car while the oil was being changed. My mechanic couldn't fin anything wrong, and the dealer never heard of such a problem. I'm trying to save $90, which is the dealer's diagnostic service charge, if I can find someone who may have experienced the same problem and has a solution I can bring with me to the dealer.

How full are you adding gas? If you add more gas after the pump automatically shuts off, that could be the cause of your problem (theoretically). My theory is that gasoline fumes, or raw gas, are going into the EVAP carbon canister; the EVAP purge valve is open (it shouldn't be); the flood of gasoline fumes are being drawn into the engine and flooding it. Good theory, eh?

There is a recall on the ball valve for the gas tank on this model. I am not sure if yours is involved or anybody has worked on it. The recall is for when the car flips then gas might leak, but it seems like most dealerships while repairing this broke something else in the process. I agree with hellokit that your gas tank is not ventilating properly. Maybe too much air stays in and the fuel pump is not getting fuel. I had bought a use '02 and could not fill-up the tank and two different dealers could not figure it out, so I returned the car at a loss, but saved myself a lot of time.

This stuff goes by other names. DRY GAS is a Cristy brand. It could also be called gas line-drier.

My theory is that maybe you have a little water in your gas tank. It happens to the best of us. Being more dense than gas, it settles in the bottom. Gasoline rushing in during a fill-up stirs up the water. Your car struggles with water in the gas until it settles out.

If it's cold where you live and it was toasty warm inside "Quicky Petroleum", and particulary if your tank was low and already had a little moisture, then going from cold to warm to cold, could have added condensation (water) to your tank.

(This is for Hello Kit, Good theory, eh? Did I miss anything?)

Whatever the outcome from all this excellent advice everybody gave, let us know what happens.

Follow the Dry Gas instructions and maybe get two. Use it for two tankfuls. Also, try letting the car sit several minutes after the first 2 fill-ups.

Francy, Or Just About Anybody For That Matter, Can Check Their Car For Recalls.

Galant has offered good advice.

Write down the VIN (Vehicle Identification Number) exactly as it is stamped on a tag at the bottom, driver's side of the dashboard where it meets the windshield, as viewed from outside the car.

Many dealers will check for "open" recalls (ones needing to be done) on cars over the telephone. They will need that VIN read to them. Most recalls are performed "free of charge" on vehicles at the dealer. Inquire about that when checking for open recalls.

Thank you for so much for your suggestion. I added a bottle of Iso-Heet (?) last night, and then, put gas in my car this morning. It was easier to get the car started after adding gas, but not back to normal. I am going to add another bottle and see what happens. I'll keep you posted.Francy

I checked the Internet, and it looks like my car is part of the recall which you mentioned. I have not had it to the dealer for that repair. I am trying the dry gas approach, and then, if that doesn't resolve the problem, I will pursue the suggestion from hellokit.Thanks,Francy

Thanks for keeping us informed. We sometimes never hear back from people. We appreciate it. Cars can be bring great joy, but you are right, at times they can be a real nuisance. Hopefully you'll get through this and be filled with joy, again!

Francy did you ever resolve this problem? I have a 2002 Sonata and am having the same exact problem. I paid $45 for the dealership to diagnose it but they said they couldn't find anything wrong. I tried the dry gas, the Iso-heet as well, but it didn't seem to make a difference. Please let me know if you resolved this and how. Thanks! Please email me at frndlyflbbw@yahoo.com when you get a chance.

So fancy, how did you get this problem resolved. Did you purchase the part or did you have the hyundai dealer replace it. I have a Hyundai Sonata 2001, GLS.. Same exact problem. It just starte happening. Mechanic said he never heard of such a problem.. How can I get the item purge control valve to replace it.. Sorry.. I am new to this but I decided I better get to know my car a little better and learn something about repairing..

I had the Hyundai dealer install the part. You could probably get the part from the parts department. If I remember, the valve was inexpensive. I paid more for the labor. (I didn't want to go to the dealer because their labor charges seem higher than the local mechanic, but the mechanic didn't know what was wrong and wasn't interested in what a girl had to say about what the problem was even though I found several sites on the internet with people describing the same issue and the same resolution.) I think it ran about 180 for parts and labor, but I don't have the invoice with me to check.Francy

I have a 2005 Hyundai 6 cyl. Runs like a champ, and 2 weeks ago, started cutting of 2 or 3 times, after adding Gas. I Googled the question, and got here, so I was wondering if anyone found a definitive answer? It only does it after having gas put in, and never close to empty, when I do it. Otherwise, it runs great. Little help?

My theory is that gasoline fumes, or raw gas, are going into the EVAP carbon canister; the EVAP purge valve is open (it shouldn't be); the flood of gasoline fumes are being drawn into the engine and flooding it. Good theory, eh?

Well, sort of. The liquid gas part anyway. The activated charcoal bed in the canister is designed to capture hydrocarbons (gas fumes) and the Purge Valve is supposed to open when you start the engine and allow the fumes to be ingested by the induction system. The problem comes when the charcoal bed is wet with liquid fuel, preventing the system from breathing properly and choking the purge system.... which, if it cannot breath in, also prevents the fumes from being ingested and the canister from purging. It's analogous to trying to breath through water. Can't be done. Saturation on some cars can happen from "topping off" the tank, a bad practice. If the OP is in the habit of doing this, I recommend that he/she discontinue the practice.

"Activated" charcoal is simply charcoal that's been washed with mild acid, making it porous. Porous materials have far surface area than nonporous materials of the same size and type. Charcoal is carbon, and carbon attracts carbon. The carbon atom is basically unstable due to deficiency in outer-orbit electrons, and is seeking to link with other carbon atoms to add to the number of electrons rotating around the atom making the atom more stable. Carbon attracts carbon very well. The adjoining atoms basically share electrons in the outer-orbit.

In short, a wet bed is a possible cause. Usually that condition will also cause a vacuum to build in the airspace in the gas tank as the gas is pumped out also, making the fuel pump struggle and ultimately die prematurely, but it could also manifest itself with the OP's symptoms.

I compliment you on your reasoning abilities. To be able to reason a problem like this out is difficult.

I'd guess that is your Hundai's evap purge valve sticking open when it should be closed. There's other possibilities but that's the place to start. You haven't been using a different place to buy gas or changed your fill-up procedure, right?

One caution if you find the problem is a stuck purge valve. That can also indicate the evap canister has failed. If you simply replace the purge valve, it will almost certainly cause the purge valve to eventually fill w/debris from the evap canister and fail again. So ask your shop to check the status of the canister too.